The invention relates to a fastening device having a fastening element, which includes a plug-in region and, at a distance therefrom, a contact surface and a shaft between the plug-in region and the contact surface. The plug-in region is able to be plugged axially through a through opening in a wall area in a plugged position of the fastening element, until the contact surface, or an intermediate part situated in between, presses against the wall area from one side and the shaft is radially centered in the through opening.
A fastening device of this type disclosed in DE 40 00 517 A1 provides a fastening element having a shaft, which has flattened areas, which, after a plug-in region of the fastening element is plugged through a through opening in the wall area until a contact surface of the fastening element presses against the wall area, work together with corresponding counter surfaces in the through opening and thus prevent twisting of the fastening element in the through opening. An axial displacement of the fastening element out of the through opening is prevented by radially elastic spring lugs on the shaft of the fastening element. The lugs engage behind an edge area of the fastening element after the fastening element is inserted into the through opening. A removal of the fastening element is thus only possible using a special tool, which radially compresses the spring lugs and is to be inserted into the through opening or possibly through it at least regionally. The insertion of the fastening element into the through opening is made more difficult, because the spring lugs are to be compressed radially elastically, working together with the edge of the insertion opening, by an axial force to be applied to the fastening element. The spring lugs may only absorb slight axial forces because of their elasticity and do not prevent a displacement of the fastening element out of the through opening in the event of greater forces. The fastening element has an axial through opening which allows a moisture transfer from one side of the wall area to the other side.
The invention provides a fastening device which reliably fixes the fastening element in the through opening even in the event of greater axial forces acting on the fastening element. The inventive fastening device may be installed and uninstalled using small forces, and may completely or at least extensively prevent moisture transfer from one side of the wall area to the other side.
According to the invention, a fastening element having a fastening device includes a plug-in region and, at a distance therefrom, a contact surface and a shaft between the plug-in region and the contact surface. The plug-in region is able to be plugged axially through a through opening in a wall area in a plugged position of the fastening element, until the contact surface, or an intermediate part situated in between, presses against the wall area from one side and the shaft is radially centered in the through opening. The fastening element is to be connected to a component, wherein the fastening element is located in its installed position if the plug-in region of the fastening element is plugged through the through opening in the plugged position and is then rotated around the axis of the shaft into an installed position delimited by a stop, in which at least one radial projection of the plug-in region engages behind an edge area of the through opening and thus prevents an axial displacement of the shaft out of the through opening, as a result of which the fastening element is fixed in the installed position.
The fastening device is thus centered radially in the through opening via its shaft and is fixed in relation to radial forces and strains in both axial directions in a formfitting way in the through opening via its contact surface and the at least one radial projection of the plug-in region plugged through the through opening and rotated into the installed position. For example, using at least one connection element, a component may therefore be connected to the wall area using at least one fastening element, for example, on which even greater radial and/or axial strains to the central axis of the shaft may act. A moisture passage from one side of the wall area to the other side may be extensively or completely prevented by a pocket hole in the fastening element, into which a threaded screw may be screwed to fasten the component on the wall area, for example. A more reliable, complete moisture transfer may at least be prevented if at least one disk seal or component seal is additionally used, for example, which is situated between an assigned side of the wall area and the fastening element and/or the component or an intermediate part.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.